Studies are continuing regarding the biochemical and virological aspects of Parkinson's Disease: This request for supplemental funds was prompted by loss of financial support from the Health Research Council of the City of New York for these projects: a) VIRAL LATENCY IN THE NERVOUS SYSTEM, and b) BIOCHEMIAL AND PHARMACOLOGICAL STUDIES OF NIGROSTRAITAL DIFFERENTIATION AND FUNCTION IN TISSUE CULTURE. Project a (Dr. Schwartz) is motivated by the hypothesis that certain slowly progressing neurological disorders, including Parkinsonism, may be caused by latent virus infection in the nervous system. herpes simplex virus (HSV) causes recurrent infection which is increasing in incidence in the population. HSV is highly neurotrophic and survives in a latent state in certain nervoud system tissues. We believe that virus infection, initiated pre- or post- nataly may eventually result in mild to severe neurological deficit. To test this hypothesis we have developed and begun to characterize experimental animals infected pre- and post- nataly with HSV. The virus persists in hamster brain for long periods and can be isolated during brain development. We propose to 1) localize the virus within brain by immunofluorescent and immunoperoxidase techniques for light and electron microscopy, and 2) determine the biochemical behavioral effects of the presence of the virus. such studies, we believe, will demonstrate how a virus infection which is common in the population can result in prolonged neurological deficiency under certain circumstances. Project b (Dr. Lehrer) utilizes organ clutures of the rodent nigro-striatal system to study trophic phenomena among the dopamine, GABA and ACh components of that system. The cultures afford more accurate and more easily interpreted information than that obtainable in experimental animals.